Answer
The amplitude ($A$) shows the maximum distance of the graph from its central line (its average value).Hence if the graph is not shifted vertically (the central line is the x-axis), then the vertical window should be at least $[-A, A]$ to include the whole graph.
The horizontal scale depends on the number of periods required ($p$), and if $t=0$ is the starting point. To show at least two periods, starting at $t=0$, the horizontal window should be at least $[0, 2p].$
Work Step by Step
The amplitude ($A$) shows the maximum distance of the graph from its central line (its average value).Hence if the graph is not shifted vertically (the central line is the x-axis), then the vertical window should be at least $[-A, A]$ to include the whole graph.
The horizontal scale depends on the number of periods required ($p$), and if $t=0$ is the starting point. To show at least two periods, starting at $t=0$, the horizontal window should be at least $[0, 2p].$
